The properties of a microwave‐induced argon plasma produced by traveling surface wave at atmospheric pressure are investigated theoretically. A hydrokinetic model is elaborated to obtain the nonequilibrium one‐dimensional profiles of electron temperatureTe(average electron energy), electron densityne, and the first excited state population densityn4s, along the axis of a steady‐state discharge. A three‐level atomic structure is assumed for the argon atom. A particle balance is included through the continuity equations forneandn4s. These equations are coupled with an energy balance equation for the electrons. The effects of different parameters on the properties of the argon discharge are investigated: discharge tube radius, gas flow rate, resonant radiation‐escape factor, and neutral gas temperature. ©1995 American Institute of Physics.